Acquisition of additional human and selected animal mammary tumor and normal cell lines. Cell line characterizations. Screening of human cell lines for M-PMV (or related) antigen. Cryopreservation of and characterization of in vivo established, transplantable human mammary tumors. Characterization of endocrine responsive tumors received from Dr. R. L. Noble, Cancer Research Centre, University of British Columbia. Establishing an indexed comprehensive bibliography of publications resulting from studies utilizing tissues obtained from the animal tumor and human cell culture bank.